Rich Man, Poor Man (1976)
S04E05 The Cleveland–Loretta Quagmire
Episode Overview
Upon hearing Loretta's scream, Peter rushes to assist, only to stumble upon the shocking truth that she's cheating on Cleveland. Realizing that Quagmire is involved, he decides he must inform Cleveland. However, when Loretta abruptly leaves Cleveland, he reacts with anger and disbelief.